How do I start disputing things on my credit report?

Write a letter to the credit bureaus disputing the charges.

Each credit bureau has instructions on their web site.

Yes, first of coure the things on your credit report that are correct should not be disbuted, ( since they are true) you dispute things that are incorrect.

Some agencies will require their forms to be used but to start you contact each reporit agency.

Do not dispute in on-line. You give up many of your rights in doing so. You can only dispute them and respond to them 3 times each within a 12 month period. Anything more than they they will usually not both to listen to. Unless you are well rehursed in there rules and requirements I would suggest your pay one of these outfits whom do this on a regular basis. IT was the best $300 I ever spent on credit repair and got me very good results.